Conventionally, in a tread pattern design of the pneumatic ti re, in order to improve the steering stability, by setting a small groove volume of a tread portion and improving rigidity of the tread land portion, a cornering power is improved and a steering response and responsiveness are achieved.
Meanwhile, in a winter tire, a snow column is formed by compacting snow on a road surface in a groove of the tread portion; and owing to a reaction force of shearing it, a driving force on snow and the like is obtained. Thus, in order to increase the snow performance, a groove volume of the winter tire is large. For example, the winter tire has a large the groove volume of a lateral groove extending axially so as to improve traction performance. A technology related to winter tire is as follows.